The Neurocritic

Wednesday, August 31, 2016

The journal Brain has a new review on the history of converting the electroencephalogram (EEG) into sound (Lutters & Koehler, 2016). The translation of data into sound, known as sonification, has been applied to brain waves since the 1930s. In addition to early scientific and medical applications, sonification of the EEG has been used in the field of experimental music.

In 1965, physicist Edmond Dewan and composer Alvin Lucier collaborated on Music for the Solo Performer:

Sitting on a chair, eyes closed, Lucier’s brainwaves were recorded from his scalp, amplified and channelled to numerous loudspeakers scattered around the room. As the amplified alpha rhythm was below the human audible range, the loudspeakers were put ‘right up against’ various percussion instruments, which were then activated by means of vibration. While Lucier attempted to refrain from mental activity, percussion sounds slowly started to fill the room, which were suddenly disrupted when he opened his eyes, engaged in mental exercise, or when his attention was drawn towards sounds from the audience (Kahn, 2013).

The article also reviews more contemporary translations of EEG activity into music:

By the end of the century, advances in EEG and sound technology ultimately gave rise to brain–computer music interfaces (BCMIs), a multidisciplinary achievement that has enhanced expressive abilities of both patients and artists (Miranda, 2014).

Image credits:

Edmond Dewan and his brainwave control system (1964). From Kahn D. Earth sound Earth signal: Energies and Earth magnitude in the arts. Los Angeles: University of California Press; 2013. p. 96. Image courtesy of Brian Dewan.

Sunday, August 28, 2016

Everything we do and feel and experience changes the brain. Psychotherapy, juggling, taxi driving, poverty, reading, drugs, art, music, anger, love. If it didn't we'd be dead. Why should prayer be any different? The trick is to accurately determine the structural or physiological changes that are unique to a specific activity. And when assessing the effectiveness of clinical interventions, how the changes compare to an adequately matched control intervention. Plenty of high profile studies have failed to do that, including a recent one on emotionally focused therapy.1

I feel bad about criticizing a study on the neural correlates of healing prayers. I'm not one of those smug atheists who lord their intellectual superiority over the unwashed religious masses. Certain atheist organizations claim they're all about promoting scientific literacy and a secular worldview. But I think these New Atheists are detrimental to science literacy, since they alienate the vast majority of the population.

So why am I blogging about a prayer intervention for depression? It's not to sneer at the authors. And it's especially not to sneer at the participants, who were recruited from Houston-area churches. My interest is the unholy alliance between brain imaging and a psychological intervention with no control condition. As I've said before...

...neuroimaging studies of psychotherapy that have absolutely no control conditions are of limited usefulness. We don't know what sort of changes would have happened over an equivalent amount of time with no intervention. More importantly, we don't know whether the specific therapy under consideration is better than another form of psychotherapy, or better than going bowling once a week.

Healing Prayer, Trauma, and Forgiveness

This is especially true for a treatment that is based on faith and a strong belief that the intervention will work — a Christian form of prayer focused on forgiveness and psycho-spiritual healing (PSFH). A prayer minister “led the subject through three different phases: (1) a prayer of forgiveness for the perpetrator of the hurtful event; (2) a prayer of blessing on the perpetrator; and (3) a prayer to heal the emotional damage caused by the traumatic event.”

The 18 participants had moderate to severe levels of depression on the Hamilton Depression Scale (HAM-D). Oddly, post-traumatic stress disorder (PTSD) was not assessed before or after the intervention. This was a major weakness, given that the purpose of the intervention was to forgive the perpetrator of childhood abuse and to heal from emotional trauma. In this sense, PSFH is akin to more formalized psychotherapies such as forgiveness therapy.

It's no surprise that a non-randomized, unblinded prayer intervention in religious persons resulted in dramatically reduced HAM-D scores in the 14 participants who completed the study (11 of whom were available for a one year followup).

Who am I to criticize a practice that helps suffering people? I won't do that.

What I will do is point out difficulties in task design that make it nearly impossible to interpret some aspects of their fMRI study. The task used a symptom provocation paradigm using 3 key words to evoke memories of the traumatic event (15 seconds) and feelings of the traumatic event (15 seconds), separated by a 2 second blank screen.2 Is it possible to separate traumatic memories from the feelings they evoke, and to switch between them on such short notice? Certain therapies (such as prolonged exposure) are designed to do just that. The authors stated that anecdotally, this appeared to be the case here as well:

In this and our previous study, subjects frequently mentioned informally that PSFH results in a separation of the traumatic memory and associated feelings: while the memory remains intact, it no longer associates with traumatic feelings.

Activity of the precuneus to Bad Feelings was higher before psycho-spiritual healing(Baldwin et al., 2016).

But to be even more fair, the authors listed ten caveats to their admittedly preliminary study.3 When all is said and done, how can this study reveal ANYTHING about the neural correlates of healing prayer?

Or in this case, nothing fails like a non-randomized, unblinded, not-placebo-controlled fMRI study of prayer. Or of any other intervention, for that matter.

2These Bad Memory/Feeling blocks were also compared to Neutral Memory/Feeling blocks that evoked memories and feelings about a neutral topic (e.g., the weather). This is the pre/post contrast shown in the first figure of the post.

“Participants were asked to press a button if they thought the person in a photo was living or deceased. Overall mean accuracy on this task was 53.8%, where 50% was expected by chance (p < 0.004, two-tail). Statistically significant accuracy was independently obtained in 5 of the 12 participants.”

The abstract claims the participants showed better than chance performance, but even if we accept this level of accuracy at face value (so to speak), the mediums were wrong 46.2% of the time. Remember that before your next psychic reading.

And of course we should not accept the results at face value. Let's take a closer look at the paper (Delorme et al., 2016), which was published in Frontiers in Human Neuroscience.

Figure 1 (Delorme et al., 2016). Process involved in creating a group of photographs of “Alive” and “Deceased” individuals.

Photographs of known alive and dead people were selected from three internet databases: (D1) school portraits from 1939–1941; (D2) school portraits from 1962–1968; and (D3) politicians (US senators excluded) and businessmen. Why? Why use pictures of US Representatives and state politicians outside of California? Even though the subjects said they didn't recognize them, there could be a vague sense of familiarity with some of these faces.

Photos of 404 individuals were presented, and the 12 participants pressed keys to indicate “deceased,” “living,” or “do not know”. 1

The participants all “claimed to be able to experience feelings of vitality from facial photographs alone. ... They were required to have been performing professional ‘readings’ for clients...” THERE WAS NO CONTROL GROUP. In other words, participants who did not claim any psychic or clairvoyant abilities were not included in this study. Thus, there was no way to know if the marginal ability to discern whether a person was alive or dead was based on mediumship.

And marginal it was. Basically, they were terrible at determining whether people in old yearbook photos were dead or alive. Terrible. No better than guessing. 2

Given the number of statistical tests, we should only consider values with *** (p<.001), of which there were two (out of 35 possible comparisons). Therefore, the evidence for mortality prediction (clairvoyance) should not be taken seriously, despite the authors' conclusion:

We do not rule out the hypothesis that subjects might have had access to information in ways that are not currently understood by modern physics and could potentially go beyond classical information delivered by facial features.

Paranormal physics do not apply to old photographs, however.

And the EEG data were equally unconvincing. The face-specific N170 component did not differ based on dead or alive, correct or incorrect. The earlier P1 component showed a small difference between correct and incorrect responses for the deceased only, but there was no good explanation for this (“Future research could assess if low-level visual image characteristics and attentional modulation were important factors in leading to this difference in electrocortical activity”).

About Me

Born in West Virginia in 1980, The Neurocritic embarked upon a roadtrip across America at the age of thirteen with his mother. She abandoned him when they reached San Francisco and The Neurocritic descended into a spiral of drug abuse and prostitution. At fifteen, The Neurocritic's psychiatrist encouraged him to start writing as a form of therapy.